Primary reinforcers have distinctive reinforcing qualities; not learned. In addition, secondary reinforcers has no inherent value and only has reinforcing qualities when linked with a primary reinforcers. The positive reinforcement is a desirable stimulus is added to increase behavior while negative reinforcement is an undesirable stimulus is removed to increase behavior.
The correct option is this: A STUDY BY DR BIRDIE SHOWED THAT THE NUMBER OF SONGBIRDS IN HER YARD INCREASED DUE TO A MODIFIED FOOD SOURCE.
A scientific claim refers to a claim that is made by a scientist due to the result that he or she obtained in the research that are conducted. In the excerpt given above, it can be seen that Dr Birdie experience influx of songbirds to her yard as a result of the dried apple and the raising that she added to the birds' food.
The Organism that the biologist observed was a part of the Porifera phylum.
B. Consisting of billions of galaxies
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